1. Field of the Invention
The invention generally relates to portable data storage devices and corresponding methods, and in particular to storing data in a non-volatile memory.
2. Description of the Related Art
Presently, a number of different flash memory cards or sticks are available on the market to allow users to store data. Flash memory (Flash-EPROM, Flash Erasable Programmable Read Only Memory) is a solid-state, non-volatile, re-writable memory that is durable, operates at low voltages, and retains data when power is off. Flash memory devices are used in digital cameras, cell phones, printers, handheld or notebook computers, pagers, audio recorders, or the like.
Flash memory cards or sticks connect the flash IC (integrated circuit) via a flash disk controller chip to the host device, i.e. a notebook, camera or the like, using an interface which requires the flash memory stick or card to be inserted into a dedicated slot or other connector. For instance, flash memory devices can be connected to host devices via a USB (Universal Serial Bus) connection. If the flash device is an SD (Secure Digital) memory card, the connection to the host device is done using an SDIO (SD Input Output) interface. Similar dedicated interfaces exist for other flash memory devices such as CF (Compact Flash) devices.
That is, taking the example of a user wishing to take pictures using a digital camera and transferring the pictures to a personal computer, the conventional techniques require the user to insert a flash memory card into the camera before taking the picture, and then remove the card from the camera and insert it into a card reader of the personal computer, or connect the camera to the computer to use the card reader of the camera.
Such handling is often found to be cumbersome. Further, since it might be necessary to frequently put the cards into the reader slots and take them out afterwards, there might occur some mechanical wear. In addition, it is not possible to use any flash memory card in any card reader which makes it sometimes difficult to transfer data from one host device to another host device.